The present disclosure relates to a method for operating a print server for digital high-capacity printing systems, as well as a corresponding print server.
Print servers for high-capacity printers are described in, for example, chapter 15 of the book “Digital Printing, Technology and Printing Techniques of Océ Digital Printing Presses”, 9th Edition, February 2005, ISBN 3-00-001081-5. Schematically shown herein is the workflow of a method used in an Océ PRISMA production document output management system for communication between two processes of a computer system for transferring print data.
Operating systems are necessary for the operation of computers. These operating systems then normally in turn include an operating system kernel as their central component. In the kernel, process and data organizations are normally established, upon which build additional software components of the operating system, and possibly of user programs. Typical requirements for a system kernel are parallel processing of different tasks, what is known as multitasking; compliance with time-critical limits; and transparency to other applications.
Kernels are normally constructed in layers, wherein the lower, machine-proximal layers form the basis for those above them. The upper layers may thereby typically call functions of the lower layers, but not vice versa.
The following layers may in particular be present, from the bottom to the top:                interface layer for hardware (e.g. input/output (I/O) devices, memory, processors),        layer for memory administration, in particular including virtual main memory        layer for process administration (scheduler)        layer for device administration (device management)        layer for administration of the file systems.        
If all of these functions or layers are integrated into the kernel itself, it is referred to as a monolithic kernel. In a microkernel, portions of this occur in separate processes. User processes also run outside of the kernel, and can operate the functions offered by the kernel in order to communicate with the aforementioned components of the computer.
Kernel hooks serve as an interface to enable the calling of a routine outside of the kernel at specific locations within a kernel. The use of kernel hooks is described in “Kernel Hook-Prozess-Filter” [“Kernel Hook Process Filter”], Walter Sprenger, IT-security-Special March 2003, Page 39 and the following, for example. With a kernel hook, a program code may be linked into an existing program. A kernel hook normally has unrestricted access to the entire system.
DE 10 2008 037 651 B4 describes a method for communication between two application programs that may be used for communication of print data in printing systems.
The exemplary embodiments of the present disclosure will be described with reference to the accompanying drawings.